If a substance cannot be broken down chemically into a simpler substance what is it

An Element

Explanation:

An element is a substance that cannot be split into smaller substance. It is made up of one kind of atom and can exist either as molecules  (e.g nitogen) or an atom (e.g argon).

an element

Explanation:

Elements are only composed of one type of atom

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.

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